A statistical evaluation model for the time-dependent strength of cement-admixed marine clay
Abstract
Deep Cement Mixing (DCM) is widely used in urban infrastructure construction such as deep excavation and tunnelling. The variability of the properties of natural soils, combined with uncertainty and inaccuracy of construction operation of deep soil mixing, leads to non-uniformity of the binder distribution in the deep cement-mixed soil, therefore, the often highly variable strength. This study investigates the point level of the unconfined compressive strength of cement-stabilized soils. A statistical approach to evaluate the heterogeneous strength of cement-admixed marine clay is proposed. The unconfined compressive strength of cemented clay is regarded as a random variable with the probability density distribution being assumed as the lognormal distribution. Particularly, the curing time effect is considered in the approach. A simple time-dependent probability density distribution is proposed, with only the mean value changing to account for the curing time effect.
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DOI: https://doi.org/10.18686/utc.v4i2.34
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